1. Field
One embodiment of the invention relates to a heat conduction member which transfers part of heat generated by a heat generation body to a region located out of the heat generation body, and an electronic device provided with the heat conduction member.
2. Description of the Related Art
The electronic device such as a portable computer contains a heat generation body such as a CPU and a north bridge (trade mark). An example of a cooling unit, which promotes the cooling of the heat generation body, includes a cooling fan, heat radiation fins, and a heat conduction member which transfers part of heat generated by the heat generation body to the heat radiation fins. A typical example of the heat conduction member is a heat pipe.
Jpn. Pat. Appln. KOKAI Publication No. 2005-77979 discloses a liquid crystal panel heat radiation structure having a heat conduction member. The liquid crystal panel heat radiation structure includes a panel heat transfer member attached with a liquid crystal panel, a panel heat sink, and a heat conduction member bridged between the panel heat transfer member and the panel heat sink. The heat conduction member is a carbon graphite sheet or a copper foil, and is flexible.
Since the heat conduction member has flexibility, unwanted reaction is little generated in the panel heat transfer member, and vibration and impact applied from outside are buffered. Therefore, distortion and displacement little occur in the liquid crystal panel.
The mounting height of the heat generation body varies depending on the kind and size of the heat generation body. The holding height of a heat radiation member also varies depending on the type of the electronic device. The heat conduction member such as the heat pipe is rigid. It is thus difficult to use one kind of the heat conduction member in the plurality of applications where the mounting heights of the heat generation bodies are different and the holding heights of the heat radiation members are different. The use of the heat conduction member is not versatile.
In recent electronic devices, a plurality of heat generation bodies requiring their cooling are frequently mounted in the case thereof. Accordingly, there has been demanded the heat conduction member capable of absorbing the difference among mounting heights of those heat generation bodies (called parts common difference). Thus, it is suitable that the heat conduction member used in recent electronic devices is flexible and is adjustable to the mounting height of the heat generation body.
The heat conduction member disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2005-77979 is a carbon graphite sheet having a thickness of about 0.2 mm obtained by laminating thin carbon sheets, or a copper foil having a thickness of about 0.1 mm. When such a heat conduction member is used, it is difficult to secure thermal conductivity. The efficiency of the heat transfer from the panel heat transfer member to the panel heat sink is not high.